Art of manufacturing steel.



BEST AVAILABLE COP.

Patented Dec. 9, 1913.

2 SHEETS-SHEET 1.

Inventor:

BEST AVAILABLE 0 I G. H. BENJAMIN. ART OF MANUFACTURING STEEL.

APPLIOATION FILED JAN. 4, 1913.

Patented Dec. 9, 1913.

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Inventor:

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BEST AVAILABLE COP UNITED STATES PATENT OFFICE.

GEORGE nrrnnnn BENJAMIN, OF NEW YORK, N. Y.

ART orrman-uracronme STEEL.

" Specification of Letters Patent.

Application filed J'anuaryA, 1913. Serial No. 740,103.

To all whom it may concern:

Be it known that I Gnoncn HILLARD BEN- JAMIN, a citizenv of the U nited States, re-' siding at New Ycrk city," iii the county and State of New York, have invented certain new and useful Improvements in the Art of Manufacturing Steelp-of which the followingis a specification; y invention relates-particularly to the treatment of molten steel by high temperatures, such as may be obtained in an electric furnace, together with suitable introd'ucedbodie's' orthe removal of phosphorus' and other bodies from theisteel.

In a prior Patent 1%.. 1,051,065 granted to "me, dated January 21st, 1913, I have described a'method of treatingsteel for the.

removahof phosphorus, etc, and p which methodinvolved the introduction of Va nous bodies which will combine with phosphorus and other-bodies at the high temperature of ail-electric nace, also heated by] electricity, andthere combined with the'necessary amount of carbon or oth' er'bodieslwhich t was'd'esi'red to introduce into the steel. method further involved the; continuous heatin 'by electricity. 4 therefromin that heating-is first efiected hy'regeneratedg'a's and. air subsequently by electricity for only"s iieh time as 1s necessary to bring about the chemical combi-.

nations betweentheintroduced bodies and, ii the bodies carried by the steel, which can-- not be efiected bythe gas and air heating;

I am aware that it has been proposed to carry out the above stated process in asingle furnace, but experience has demonstrated that" it'is practically impossible to thus eliminate the necessary amount of phosphorus and other'materials,-Iand that this is due to the fact that steel'cannot 'be com pleteiy slaggedin a single furnace. To overcome the difiiculties aboveset-forth, I

. proceed in theinanner which I will now describe, and make use .of;, a;;kparatus such .yi r was is ustrated in'the a v pricidescribleld (iin the specification."

e erri to to raw'm' gs E i re 1 reprenenits il -gen view'ofian 'arra g emeiit of furnaces adapted to carry my invention into 'efieet-.Fig: 2a, a vertical sect-ion of anelectric furnace, Ia side, and vertical section ofaigas aside elevation of: the

elevation of -vation of a mixer, taken on the line III-III I of Fig. l.

arc, after which", purified metal Was-run into a second 'furt My present method d ffers hood'of a gas furnace as rembved from the hearth, taken on the line IIII of Fig. 1 looking from the left. Fig. 3 is a vertical section of a gas furnace, a side elevation of vthe hearth etached from the roof, a side a gas furnace, and side elej It will be understood from reference to the ;figu res, that they are ln'a sense diagrammatic and intended not only to show the general construction of the furnaces, but e' relation of the. furnaces to eachother,

1nd also the relation of the movable hearths I Referring to thedrawings; 5 represents a mixer ofi-the usual construction, mounted on attack 6 and'provided with means 7,

consistin of a 'c linden and piston operated -by a mot ve flui for tilting the mixer.

of the. burners 15, and the hoods' 14 through the medium'of'the adjustable electrodes 16.

Te hoodsliiiandil occupy a fixed relai 'lrertically,-by; ineans 17 consisting of 2. cylindercand piston operated by a motive fluid. Regeneratedga's and air is introduced to the burners 15 through the pipes 1819,

Patented Dec. 9,1913.

byj a motive fluid. Located and'9, area series'of fixed hoods 13 and n-i te the'trackways, but are adjustable which are supplied with suitable valves for controlling the gas-"and air. As the arrangement of the pipes for gas and air and the controlling valves may be altered, no specific description is. thought necessary of those shown in the drawings.

20" represents. a 'ladle' for receiving the molten steel in a finished condition, and 21 slag troughs My improved method and the operation 1 of the structure shown and described, may

be effected as follows: Bessemerized iron,

from which'silicon, carbon and phosphorus has been partiall' removed .in a'converter (not shown) is ischarged into the m xer 5, and from the mixer 5 (shown at the right hand side offigfl) into onooi the movable- 11c BEST AVAILABLE COP.

hearths 11, which at the time is under one of the gas-hoods 13 (shown at the right hand side of Fig. 2), the purpose of which is to keep' the metal hot. If desired, at this time an oxidizing basic flux may be charged upon the metal on the hearth. As soon as the hearth is filled, the hood 13 is raised (as shown at the right of Fig. 3) and the hearth moved along trackway 9' to the position of the gas hood 13 at the right of the mixer.

Here it is held for a time under the in fluence of the heat in the gas hood, when further flux may be introduced. The slag is then withdrawn and the hearth moved under the electric hood 1-1, and lime or lime and carbon introduced, which, under the It will be understood that as the first mentioned-hearth (designated by the letter A) is moved from themixing position, a previously emptied hearth (designated by the letter B) is moved into the position formerly occupied by A, along the trackway 8 to be filled, and then moved progressively along the traclrway 8 under the successive hearths to the discharging position.

It will be observed from the description, that in moving from the fillingposition to the second position (designated by the letter S at the right and left) the temperature is such as may be maintained by gas and air with the consequent known reactions, as usual in a'basic open hearth furnace, and that when moved to the third position (designated by the letter T at the ri ht and left) the temperature is such as to e ect all the reactions usual in an electric furnace, and whenmoved to the discharging position (designated by the letter D) the temperature' is such as te-ma-intairrtWmetal sufiiciently fluid to pour.

In Fig. .1 of the drawing, the trackway is illustrated as open, that is, the hearths in moving from one position to. the next, are exposed to the atmosphere. Manifestly the trackway may .be inclosed (as indicated in dotted lines on the upper right hand corner of Fig. 1) so as toprevent the escape of heat, and further, any mechanical means may be employed to move the hearths u on the trackway. Further; the hearths, w ile in definite positions or at any part of the trackway, may be cleaned ofslag, the removal ofthe hearths from the hoods allowing unusual facilitiesfor removing the slag.

It will be understood from the description as far as given,that the steps'involving the carrying out of the above process are I as follows: first: pouring the metal on to a hearth; then fluxing and subjecting to the temperature such as may be obtained from the regenerated gas. and air; then moving the hearth to the second position and again subjecting it to the temperatureof regenmoving the highly heated cleaned or slagged metal into the third position, introducing lime, and there subjecting it to the. high temperature and other efi'ects of transmitted electric current to produce final separation of the phosphorus, carbon and other separable materials; then again removing slag and finally moving to the discharging position, there introducing carbon and finally discharging into a ladle or other device.

It will be understood by those skilled in the art to which this invention belongs, that the hearths may have an acid or basic lining, depending upon the treatment to which the material is to be subjected. Further, that fiuXing may be accomplished with all known fluxes. Further that the temperature effects of the electric current may be obtained either by means of electrodes dipping into the fused material on the hearth thereby; heating by resistance; or partially dipping intogthe material and thereby heating partially by an arc and par tially by resistance; or that'in place of electrodes, heating might be accomplished by induction, it being within the-intent of the invention to use any method of electric heating' which will produce the'necessary chemical reactions when the -hearths are in the third position,

It'will be further understood that the major portion of the heat necessary to produce the requisite reactions is created by the combustion of gas and air and that only a small amount of electrical energyis necessary to raise the temperature of the metal on the hearths when under the electric hoods,

place which are not possible under the temperatures produced by as and air, thus efiecting a great savin in the cost of the electrical ener -ess. Further, t at owing to the disposition of the hearths as shown in the drawings, rapidity, of action and facility of manufacturing is acquired over known methods where attempts have been made to produce the necessary successive reactions, firstby the influence of heat through gas and air, and then by electricity in, the same furnace. Further, that by reason of the system of movable jhearths and fixed hoods, the wear and tear on the hearths and hoods is greatly diminished.

Having thus described my invention, I claim:

1. An improvement in the art of manufacturing steel which consists in charging erated gas and air and again fiuxing; thento that wherein chemical actions may take" and c eapiening the proc- I BEST AVAILABLE COP.

inoltenf bessemeri'zed ironfon. to heated hearth, introducing a flux, subjecting the. iron-1 and flux to the action of a gaseous atmosphere and" a-temper'ature due to the combustion of gas'and' air, thenremoving the slag produced, then. movingithe'hearth andthe metal out of the gaseous atmosphere and temperature, then introducing a" ,difierent flux .t'o jafhigh temperature due to theeflt'ect 'ofan electric current, then introducing-car "bonj'and finally. pouring steel.

molten iron irom" which phosphorus, carbon and siliconhave been partially removed by onidatio n' on to a heated hearth,introducing a basicflux-and then subjecting the iron and flux to the actionof a gaseous atmosphere and'a temperature sufficiently high to eiiect a further removal of the phosphorus, carbon and silicon, then removing the slag produced, then moving. the hearth and the purifiedv iron thereon out of the gaseous atmosphere and temperature, then introducing,

lime, then subjecting the purified iron and the lime to a temperature sufiiciently high to bring aboutcombination of the remaining phosphorus, carbon and silicon w-ith'the lime, then removing the slag, then introducing the required percentage of carbon, and

v finally pouring steel.

3. An improvement in theart of. manufacturing steel which consists in charging molten bessemerized iron on to a heated hearth, then introducing a flux, then subjecting the iron and flux tora gaseous atmos phere and temperature due to the combustion of gas andai'r sufficient to' bring about a partial combination with the flux of the phosphorus, carbon and silicon carriedxby the iron, then slag ging, then moving the hearth and thepurified iron thereon out of the gaseous atmosphere and temperature, 45.

then introducing a lime flux, then subjecting-- the purified iron-and'flux to the temperature effects of an electric current, then 'slagging,

then moving the hearth and'purified iron thereon into a reducing atmosphere due to Gopie: of this patent may be obtained for fAn improvement-int facturingsteel which consists in charging- 2.';An mprovement in the art of' manu- -facturing' steel which consists in charging the c o rnb ustio'n of gas-and air, then introducingic'arbon, and finallyplouring the steel.

molten bessemeri'zed iron on to a heated hearth heated bjr-a gas and air flame, then e art of manuintroducingjfa flux, .then moving the hearth,

and the purified iron thereon and again sub'- .jectingthe i ron'to the action of a gas and air flame. having a different temperature;

then moving the hearth and the iron thereon out of the influence of the gaseous atmosphere and-temperature, then slaggin then moving the hearth and purified iront ereon, 'th'eninti'odu'cing lime, then subjecting the.

purified iron and lime to the action of 'a temperature due toa' transmitted electric current, then' slagging, then'vagain moving the hearth and the purified iron thereon, then introducing carbon, then again subjecting the purified iron and carbon to a gaseous atmosphere and temperature, and

finally pouring steel. I

5. The herein described method of converting bessemerized iron into steel, which consists in first subjectingthe iron to the ""action of a flux, a reducing atmosphere and the temperature effects due to the combustion'of gas and air, then slagging, then moving the purified iron from the reducing atmosphere and out of the presence of any bodies which-would tend to combine again with the iron, and subjectingit to a temperature due to the combustion of gas and air, then introducing lime, then subjecting GEORGE HILLARD BENJA IN.

Witnesses:

' I'IELEN E. KonLscH,

MAnonL MULET.

five cents each, by addressing the Commissioner of latenti, washingtorn'D. c. 

